If I will do it by myself (outside of blender) this will be my understanding.
In a video is there a reason why Top View become the Screen & buttons? or is this just a personal chooses? do we even need to worry about how to chose which one assigned to which direction? (assuming the reference image is given, like what we have in this course)
I think it's a matter of preference... Typically, though, either front or top view is used as the "frame of reference". In this case, top view was likely used because if you see a handheld game console sitting on a table face up... that would be like looking at it from "top view", so that would be the frame of reference all the local axes would use. In this case, if you used "front view" then the "default" position would be of it standing up on it's end.
